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From: vjudeu@gazeta.pl
To: ZmnSCPxj <ZmnSCPxj@protonmail.com>
Date: Sun, 17 Oct 2021 09:24:43 +0200
Message-Id: <118811322-c002f9f41f003a55807feca44f9160a2@pmq8v.m5r2.onet>
Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Year 2038 problem and year 2106 chain halting
Precedence: list

> Then starting at Unix Epoch 0x80000000, post-softfork nodes just incremen=
t the timestamp by 1 on each new block.

It is possible to go even faster. The fastest rate is something like that, =
if you assume the time in the Genesis Block is zero:

0 1 2 2 3 3 3 3 4 4 4 4 4 4 5 5 5 5 5 5 6 ...

Then you can increment timestamps once per 6 blocks, that means x3600 incre=
ase, but then the difficulty is always multiplied by four, so you have to i=
ncrease time once per difficulty change to keep it on real level, then it w=
ill wave between being multiplied by 4 and by 0.25.

On 2021-10-17 01:23:24 user ZmnSCPxj <ZmnSCPxj@protonmail.com> wrote:
> Good morning vjudeu,

> > What happens if a series of blocks has a timestamp of 0xFFFFFFFF at the=
 appropriate time?
>
> The chain will halt for all old clients, because there is no 32-bit value=
 greater than 0xffffffff.
>
> > 1.  Is not violated, since "not lower than" means "greater than or equa=
l to"
>
> No, because it has to be strictly "greater than" in the Bitcoin Core sour=
ce code, it is rejected when it is "lower or equal to", see:https://github.=
com/bitcoin/bitcoin/blob/6f0cbc75be7644c276650fd98bfdb6358b827399/src/valid=
ation.cpp#L3089-L3094

Then starting at Unix Epoch 0x80000000, post-softfork nodes just increment =
the timestamp by 1 on each new block.
This just kicks the can since that then imposes a limit on the maximum numb=
er of blocks, but at least the unit is now ~10 minutes instead of 1 second,=
 a massive x600 increase in the amount of time we are forced to hardfork.

On the other hand, this does imply that the difficulty calculation will bec=
ome astronomically and ludicrously high, since pre-softfork nodes will thin=
k that blocks are arriving at the rate of 1 per second, so ...

Regards,
ZmnSCPxj